These harmless looking mugs offer a great joke to play on unsuspecting victims.

At first glance these look like ordinary but handsome coffee mugs. However, when anyone raises them to their lips to take a drink a cheeky message on the mug's base will be revealed! Printed on the base of the mug is either 'I'm a Twat' or 'Office B*tch'. Everyone except the drinker will be able to see it when they take a swig.

So, when it's your turn to make the coffee, you can choose who to give the Surprise Mug too, so that everyone else can have a snigger at their expense! Will you be able to keep from laughing at them? Half the fun is not letting on!